/* 世纪人物杂志官网 - 全局样式 */

:root {
    /* 品牌主色 */
    --primary: #B8860B;
    --primary-dark: #8B6914;
    --primary-light: #DAA520;
    
    /* 辅助色 */
    --accent: #C41E3A;
    --accent-dark: #8B0000;
    
    /* 中性色 */
    --dark: #1a1a1a;
    --gray: #666;
    --light-gray: #f5f5f5;
    --white: #fff;
    
    /* 字体 */
    --font-heading: "Noto Serif SC", "SimSun", serif;
    --font-body: "Noto Sans SC", "Microsoft YaHei", sans-serif;
    
    /* 间距 */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 2rem;
    --spacing-xl: 4rem;
    
    /* 阴影 */
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.1);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 25px rgba(0,0,0,0.15);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-body);
    color: var(--dark);
    line-height: 1.8;
    background: var(--white);
}

a {
    color: inherit;
    text-decoration: none;
    transition: color 0.3s;
}

a:hover {
    color: var(--primary);
}

img {
    max-width: 100%;
    height: auto;
}

/* 容器 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* 头部 */
.header {
    background: var(--white);
    border-bottom: 1px solid #eee;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-top {
    background: var(--dark);
    color: var(--white);
    padding: var(--spacing-sm) 0;
    font-size: 0.85rem;
}

.header-top a {
    color: var(--white);
}

.header-main {
    padding: var(--spacing-md) 0;
}

.logo {
    font-family: var(--font-heading);
    font-size: 2rem;
    font-weight: bold;
    color: var(--primary);
}

.logo span {
    color: var(--accent);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-lg);
}

.nav-menu a {
    font-weight: 500;
    padding: var(--spacing-sm) 0;
    border-bottom: 2px solid transparent;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: var(--primary);
    border-bottom-color: var(--primary);
}

/* 滚动新闻 */
.news-ticker {
    background: linear-gradient(90deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: var(--white);
    padding: var(--spacing-sm) 0;
    overflow: hidden;
}

.ticker-label {
    background: var(--accent);
    padding: var(--spacing-xs) var(--spacing-sm);
    display: inline-block;
    font-weight: bold;
    margin-right: var(--spacing-md);
}

.ticker-content {
    display: inline-block;
    white-space: nowrap;
    animation: ticker 30s linear infinite;
}

@keyframes ticker {
    0% { transform: translateX(100%); }
    100% { transform: translateX(-100%); }
}

/* 英雄区域 */
.hero {
    position: relative;
    height: 500px;
    overflow: hidden;
}

.hero-slide {
    position: absolute;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 1s;
}

.hero-slide.active {
    opacity: 1;
}

.hero-slide img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.hero-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(to right, rgba(0,0,0,0.8) 0%, transparent 60%);
    display: flex;
    align-items: center;
}

.hero-content {
    color: var(--white);
    max-width: 500px;
    padding: var(--spacing-lg);
}

.hero-badge {
    background: var(--accent);
    padding: var(--spacing-xs) var(--spacing-sm);
    display: inline-block;
    margin-bottom: var(--spacing-md);
}

.hero-title {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    line-height: 1.3;
    margin-bottom: var(--spacing-md);
}

.hero-meta {
    font-size: 0.9rem;
    opacity: 0.8;
    margin-bottom: var(--spacing-md);
}

.hero-btn {
    background: var(--primary);
    color: var(--white);
    padding: var(--spacing-sm) var(--spacing-lg);
    display: inline-block;
    font-weight: bold;
    border: none;
    cursor: pointer;
    transition: background 0.3s;
}

.hero-btn:hover {
    background: var(--primary-dark);
    color: var(--white);
}

/* 区块标题 */
.section-title {
    font-family: var(--font-heading);
    font-size: 1.8rem;
    color: var(--primary);
    text-align: center;
    margin-bottom: var(--spacing-lg);
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 3px;
    background: var(--primary);
    margin: var(--spacing-sm) auto 0;
}

/* 封面人物 */
.cover-section {
    padding: var(--spacing-xl) 0;
    background: var(--light-gray);
}

.cover-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-lg);
    align-items: center;
}

.cover-image {
    position: relative;
    overflow: hidden;
}

.cover-image img {
    width: 100%;
    transition: transform 0.5s;
}

.cover-image:hover img {
    transform: scale(1.05);
}

.cover-badge {
    position: absolute;
    top: var(--spacing-md);
    left: var(--spacing-md);
    background: var(--accent);
    color: var(--white);
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: 0.85rem;
}

.cover-info h2 {
    font-family: var(--font-heading);
    font-size: 2rem;
    color: var(--primary);
    margin-bottom: var(--spacing-sm);
}

.cover-info .issue-no {
    color: var(--gray);
    margin-bottom: var(--spacing-md);
}

.cover-info .excerpt {
    margin-bottom: var(--spacing-md);
    color: var(--gray);
}

.btn-primary {
    background: var(--primary);
    color: var(--white);
    padding: var(--spacing-sm) var(--spacing-lg);
    display: inline-block;
    font-weight: bold;
    border: none;
    cursor: pointer;
    transition: background 0.3s;
}

.btn-primary:hover {
    background: var(--primary-dark);
    color: var(--white);
}

/* 文章网格 */
.articles-section {
    padding: var(--spacing-xl) 0;
}

.articles-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
}

.article-card {
    background: var(--white);
    border: 1px solid #eee;
    overflow: hidden;
    transition: box-shadow 0.3s, transform 0.3s;
}

.article-card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-5px);
}

.article-card .cover {
    height: 200px;
    overflow: hidden;
}

.article-card .cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s;
}

.article-card:hover .cover img {
    transform: scale(1.1);
}

.article-card .content {
    padding: var(--spacing-md);
}

.article-card .category {
    color: var(--accent);
    font-size: 0.85rem;
    margin-bottom: var(--spacing-sm);
}

.article-card h3 {
    font-family: var(--font-heading);
    font-size: 1.2rem;
    margin-bottom: var(--spacing-sm);
    line-height: 1.4;
}

.article-card .meta {
    font-size: 0.85rem;
    color: var(--gray);
}

/* 页脚 */
.footer {
    background: var(--dark);
    color: var(--white);
    padding: var(--spacing-xl) 0 var(--spacing-md);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.footer h4 {
    color: var(--primary-light);
    margin-bottom: var(--spacing-md);
    font-size: 1.1rem;
}

.footer ul {
    list-style: none;
}

.footer ul li {
    margin-bottom: var(--spacing-sm);
}

.footer ul a {
    color: rgba(255,255,255,0.7);
}

.footer ul a:hover {
    color: var(--primary-light);
}

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding-top: var(--spacing-md);
    text-align: center;
    font-size: 0.85rem;
    color: rgba(255,255,255,0.5);
}

/* 页面标题 */
.page-header {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: var(--white);
    padding: var(--spacing-xl) 0;
    text-align: center;
}

.page-header h1 {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
}

.page-header p {
    opacity: 0.9;
}

/* 表单样式 */
.form-group {
    margin-bottom: var(--spacing-md);
}

.form-group label {
    display: block;
    margin-bottom: var(--spacing-xs);
    font-weight: 500;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: var(--spacing-sm);
    border: 1px solid #ddd;
    font-size: 1rem;
    font-family: inherit;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
}

/* 响应式 */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }
    
    .hero {
        height: 400px;
    }
    
    .hero-title {
        font-size: 1.8rem;
    }
    
    .cover-wrapper {
        grid-template-columns: 1fr;
    }
    
    .articles-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
    }
}

/* 订阅方案 */
.pricing-cards {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
    margin: var(--spacing-xl) 0;
}

.pricing-card {
    background: var(--white);
    border: 2px solid #eee;
    padding: var(--spacing-lg);
    text-align: center;
    transition: border-color 0.3s, box-shadow 0.3s;
}

.pricing-card:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-lg);
}

.pricing-card.featured {
    border-color: var(--primary);
    transform: scale(1.05);
}

.pricing-card h3 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    margin-bottom: var(--spacing-sm);
}

.pricing-card .price {
    font-size: 2.5rem;
    font-weight: bold;
    color: var(--primary);
    margin-bottom: var(--spacing-md);
}

.pricing-card .price span {
    font-size: 1rem;
    color: var(--gray);
}

.pricing-card ul {
    list-style: none;
    margin-bottom: var(--spacing-lg);
}

.pricing-card li {
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid #eee;
}

/* 加载动画 */
.loading {
    text-align: center;
    padding: var(--spacing-lg);
    color: var(--gray);
}

.spinner {
    width: 40px;
    height: 40px;
    border: 3px solid #eee;
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto var(--spacing-md);
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* 空状态 */
.empty-state {
    text-align: center;
    padding: var(--spacing-xl);
    color: var(--gray);
}

.empty-state img {
    width: 120px;
    margin-bottom: var(--spacing-md);
    opacity: 0.5;
}

/* 期刊存档 */
.archives-section {
    padding: var(--spacing-xl) 0;
}

.archives-year {
    margin-bottom: var(--spacing-xl);
}

.archives-year h3 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    color: var(--primary);
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 2px solid var(--primary);
}

.issues-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-lg);
}

.issue-card {
    background: var(--white);
    border: 1px solid #eee;
    overflow: hidden;
    transition: box-shadow 0.3s;
}

.issue-card:hover {
    box-shadow: var(--shadow-md);
}

.issue-card .cover {
    height: 280px;
    overflow: hidden;
}

.issue-card .cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.issue-card .content {
    padding: var(--spacing-md);
}

.issue-card h4 {
    font-family: var(--font-heading);
    margin-bottom: var(--spacing-xs);
}

.issue-card .issue-no {
    color: var(--gray);
    font-size: 0.85rem;
}

/* 封面人物页面 */
.covers-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
    margin-top: var(--spacing-lg);
}

.cover-card {
    background: var(--white);
    border: 1px solid #eee;
    overflow: hidden;
    transition: transform 0.3s, box-shadow 0.3s;
}

.cover-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.cover-card .cover-image {
    height: 350px;
    overflow: hidden;
}

.cover-card .cover-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.cover-card .info {
    padding: var(--spacing-md);
}

.cover-card h3 {
    font-family: var(--font-heading);
    font-size: 1.3rem;
    color: var(--primary);
    margin-bottom: var(--spacing-xs);
}

.cover-card .issue-info {
    color: var(--gray);
    font-size: 0.85rem;
}

.cover-card .description {
    margin-top: var(--spacing-sm);
    color: var(--gray);
    font-size: 0.9rem;
}

/* 关于页面 */
.about-section {
    padding: var(--spacing-xl) 0;
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xl);
    align-items: center;
}

.about-text h2 {
    font-family: var(--font-heading);
    font-size: 1.8rem;
    color: var(--primary);
    margin-bottom: var(--spacing-md);
}

.about-text p {
    margin-bottom: var(--spacing-md);
    line-height: 2;
}

.about-image img {
    width: 100%;
    box-shadow: var(--shadow-lg);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-lg);
    margin: var(--spacing-xl) 0;
}

.stat-item {
    text-align: center;
    padding: var(--spacing-lg);
    background: var(--light-gray);
}

.stat-item .number {
    font-size: 3rem;
    font-weight: bold;
    color: var(--primary);
    font-family: var(--font-heading);
}

.stat-item .label {
    color: var(--gray);
    margin-top: var(--spacing-sm);
}

/* 联系页面 */
.contact-section {
    padding: var(--spacing-xl) 0;
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xl);
}

.contact-info h3 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    color: var(--primary);
    margin-bottom: var(--spacing-md);
}

.contact-item {
    display: flex;
    align-items: flex-start;
    margin-bottom: var(--spacing-md);
}

.contact-item .icon {
    width: 40px;
    height: 40px;
    background: var(--primary);
    color: var(--white);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: var(--spacing-md);
}

.contact-form h3 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    color: var(--primary);
    margin-bottom: var(--spacing-md);
}

.contact-form button {
    width: 100%;
}

/* 分类筛选 */
.category-filter {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
}

.category-btn {
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--light-gray);
    border: 1px solid #eee;
    cursor: pointer;
    transition: all 0.3s;
}

.category-btn:hover,
.category-btn.active {
    background: var(--primary);
    color: var(--white);
    border-color: var(--primary);
}

/* 分页 */
.pagination {
    display: flex;
    justify-content: center;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-xl);
}

.pagination a,
.pagination span {
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid #eee;
    display: inline-block;
}

.pagination a:hover {
    background: var(--primary);
    color: var(--white);
    border-color: var(--primary);
}

.pagination .current {
    background: var(--primary);
    color: var(--white);
    border-color: var(--primary);
}

/* 文章详情 */
.article-detail {
    max-width: 800px;
    margin: 0 auto;
}

.article-header {
    text-align: center;
    padding: var(--spacing-xl) 0;
}

.article-header .category {
    color: var(--accent);
    margin-bottom: var(--spacing-md);
}

.article-header h1 {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    color: var(--dark);
    margin-bottom: var(--spacing-md);
    line-height: 1.3;
}

.article-header .meta {
    color: var(--gray);
}

.article-cover {
    margin-bottom: var(--spacing-xl);
}

.article-cover img {
    width: 100%;
    max-height: 500px;
    object-fit: cover;
}

.article-body {
    font-size: 1.1rem;
    line-height: 2;
}

.article-body p {
    margin-bottom: var(--spacing-md);
}

.article-body h2 {
    font-family: var(--font-heading);
    color: var(--primary);
    margin: var(--spacing-lg) 0 var(--spacing-md);
}

/* 响应式调整 */
@media (max-width: 992px) {
    .issues-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .covers-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .about-content,
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .pricing-cards {
        grid-template-columns: 1fr;
    }
    
    .pricing-card.featured {
        transform: none;
    }
}

@media (max-width: 768px) {
    .issues-grid,
    .covers-grid {
        grid-template-columns: 1fr;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .hero {
        height: 350px;
    }
    
    .hero-title {
        font-size: 1.5rem;
    }
    
    .article-header h1 {
        font-size: 1.8rem;
    }
}

/* 导航搜索框 */
.header-search {
    display: flex;
    align-items: center;
    margin-left: var(--spacing-lg);
}

.header-search input {
    padding: 8px 12px;
    border: 1px solid #ddd;
    border-radius: 4px 0 0 4px;
    width: 180px;
    font-size: 0.9rem;
}

.header-search button {
    padding: 8px 16px;
    background: var(--primary);
    color: white;
    border: none;
    border-radius: 0 4px 4px 0;
    cursor: pointer;
    font-size: 0.9rem;
}

.header-search button:hover {
    background: var(--primary-dark);
}

/* 搜索页面 */
.search-section {
    max-width: 600px;
    margin: 0 auto var(--spacing-xl);
}

.search-bar {
    display: flex;
    gap: 0;
}

.search-bar input {
    flex: 1;
    padding: 14px 20px;
    border: 2px solid #ddd;
    border-radius: 8px 0 0 8px;
    font-size: 1rem;
}

.search-bar button {
    padding: 14px 30px;
    background: var(--primary);
    color: white;
    border: none;
    border-radius: 0 8px 8px 0;
    cursor: pointer;
    font-size: 1rem;
    transition: background 0.3s;
}

.search-bar button:hover {
    background: var(--primary-dark);
}

.page-header {
    text-align: center;
    padding: var(--spacing-xl) 0;
}

.page-header h1 {
    font-family: var(--font-heading);
    font-size: 2rem;
    color: var(--primary);
    margin-bottom: var(--spacing-sm);
}

.page-header p {
    color: var(--gray);
}

.empty-state {
    text-align: center;
    padding: var(--spacing-xl);
    color: var(--gray);
}

.loading {
    text-align: center;
    padding: var(--spacing-xl);
    color: var(--gray);
}

/* 文章卡片悬停效果 */
.article-card {
    transition: transform 0.3s, box-shadow 0.3s;
}

.article-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

/* 相关推荐 */
.related-section {
    margin-top: var(--spacing-xl);
    padding-top: var(--spacing-xl);
    border-top: 1px solid #eee;
}

.related-section h3 {
    font-family: var(--font-heading);
    color: var(--primary);
    margin-bottom: var(--spacing-md);
}

.related-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-md);
}

.related-item {
    background: var(--light-gray);
    padding: var(--spacing-md);
    border-radius: 4px;
    transition: background 0.3s;
}

.related-item:hover {
    background: #e8e8e8;
}

.related-item h4 {
    font-size: 0.95rem;
    color: var(--dark);
    margin-bottom: 0;
}

.related-item a {
    color: inherit;
}

/* =====================
   移动端响应式优化
   ===================== */

/* 移动端菜单按钮 */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 28px;
    height: 20px;
    cursor: pointer;
    position: absolute;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
}

.mobile-menu-btn span {
    display: block;
    width: 100%;
    height: 3px;
    background: var(--primary);
    border-radius: 2px;
    transition: all 0.3s;
}

.mobile-menu-btn.active span:nth-child(1) {
    transform: rotate(45deg) translate(6px, 6px);
}

/* =====================
   期刊在线阅读
   ===================== */

/* 期刊卡片在线阅读按钮 */
.issue-card .issue-cover {
    position: relative;
    overflow: hidden;
}

.issue-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(196, 30, 58, 0.85);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity 0.3s;
}

.issue-card .issue-cover:hover .issue-overlay {
    opacity: 1;
}

.issue-overlay .read-btn {
    color: white;
    font-size: 14px;
    padding: 8px 16px;
    border: 2px solid white;
    border-radius: 20px;
    transition: all 0.3s;
}

.issue-overlay .read-btn:hover {
    background: white;
    color: var(--primary);
}

.issue-actions {
    display: flex;
    gap: 10px;
    margin-top: 10px;
}

.issue-actions .read-more {
    flex: 1;
    text-align: center;
    padding: 8px 12px;
    font-size: 13px;
    background: var(--primary);
    color: white;
    border-radius: 4px;
    text-decoration: none;
    transition: background 0.3s;
}

.issue-actions .read-more:hover {
    background: var(--primary-dark);
}

.issue-actions .read-more.secondary {
    background: #f0f0f0;
    color: #333;
}

.issue-actions .read-more.secondary:hover {
    background: #e0e0e0;
}

.icon-read::before {
    content: "📖";
    margin-right: 5px;
}

.mobile-menu-btn.active span:nth-child(2) {
    opacity: 0;
}

.mobile-menu-btn.active span:nth-child(3) {
    transform: rotate(-45deg) translate(6px, -6px);
}

/* 平板端 (768px - 1024px) */
@media (max-width: 1024px) {
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .header-main {
        padding: var(--spacing-sm) 0;
    }
    
    .logo {
        font-size: 1.5rem;
    }
    
    .nav-menu {
        gap: var(--spacing-md);
    }
    
    .nav-menu a {
        font-size: 0.9rem;
    }
    
    .hero {
        height: 450px;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .articles-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .cover-wrapper {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .pricing-cards {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .pricing-card.featured {
        grid-column: span 2;
        transform: scale(1);
    }
    
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .related-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* 手机端 (768px 及以下) */
@media (max-width: 768px) {
    /* 移动端菜单 */
    .mobile-menu-btn {
        display: flex;
    }
    
    .header-main {
        position: relative;
        display: flex;
        justify-content: space-between;
        align-items: center;
    }
    
    .nav-menu {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--white);
        flex-direction: column;
        gap: 0;
        box-shadow: var(--shadow-md);
        display: none;
        z-index: 99;
    }
    
    .nav-menu.active {
        display: flex;
    }
    
    .nav-menu li {
        border-bottom: 1px solid #eee;
    }
    
    .nav-menu a {
        display: block;
        padding: var(--spacing-sm) var(--spacing-md);
        border-bottom: none;
    }
    
    .nav-menu a:hover,
    .nav-menu a.active {
        background: var(--light-gray);
        border-bottom: none;
    }
    
    /* 头部搜索 */
    .header-search {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 40px;
        padding: var(--spacing-sm);
        background: var(--white);
        z-index: 100;
    }
    
    .header-search.active {
        display: block;
    }
    
    .header-search input {
        width: 100%;
        padding: var(--spacing-sm);
        border: 1px solid #ddd;
        border-radius: 4px;
    }
    
    /* 滚动新闻 */
    .news-ticker {
        font-size: 0.8rem;
    }
    
    .ticker-label {
        padding: 2px 6px;
        font-size: 0.75rem;
    }
    
    /* 英雄区域 */
    .hero {
        height: 350px;
    }
    
    .hero-title {
        font-size: 1.5rem;
        padding: 0 var(--spacing-sm);
    }
    
    .hero-excerpt {
        font-size: 0.9rem;
        padding: 0 var(--spacing-sm);
    }
    
    .slide-dots {
        bottom: 10px;
    }
    
    .dot {
        width: 8px;
        height: 8px;
    }
    
    /* 区块标题 */
    .section-title {
        font-size: 1.3rem;
    }
    
    /* 文章卡片 */
    .articles-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }
    
    .article-card {
        flex-direction: column;
    }
    
    .article-card-image {
        width: 100%;
        height: 180px;
    }
    
    .article-card-content {
        padding: var(--spacing-sm);
    }
    
    .article-card h3 {
        font-size: 1rem;
    }
    
    /* 封面人物 */
    .cover-wrapper {
        grid-template-columns: 1fr;
    }
    
    .cover-main {
        order: 1;
    }
    
    .cover-thumbs {
        order: 2;
        flex-direction: row;
        overflow-x: auto;
    }
    
    /* 期刊网格 */
    .issues-grid,
    .covers-grid {
        grid-template-columns: 1fr;
    }
    
    .issue-card {
        flex-direction: column;
    }
    
    .issue-cover {
        width: 100%;
        height: 200px;
    }
    
    /* 订阅方案 */
    .pricing-cards {
        grid-template-columns: 1fr;
    }
    
    .pricing-card.featured {
        grid-column: span 1;
    }
    
    .pricing-card .price {
        font-size: 2rem;
    }
    
    /* 统计数据 */
    .stats-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }
    
    .stat-item {
        padding: var(--spacing-md);
    }
    
    /* 页脚 */
    .footer-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-lg);
    }
    
    .footer-links {
        flex-direction: column;
        gap: var(--spacing-sm);
    }
    
    /* 关于页面 */
    .team-grid {
        grid-template-columns: 1fr;
    }
    
    .timeline::before {
        left: 20px;
    }
    
    .timeline-item {
        padding-left: 50px;
    }
    
    .timeline-marker {
        left: 10px;
    }
    
    /* 联系页面 */
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .contact-info {
        flex-direction: column;
    }
    
    /* 文章详情 */
    .article-header {
        padding: var(--spacing-md);
    }
    
    .article-header h1 {
        font-size: 1.5rem;
        line-height: 1.4;
    }
    
    .article-meta {
        flex-wrap: wrap;
        gap: var(--spacing-sm);
    }
    
    .article-content {
        padding: var(--spacing-md);
        font-size: 0.95rem;
        line-height: 1.8;
    }
    
    .related-grid {
        grid-template-columns: 1fr;
    }
    
    /* 搜索结果 */
    .search-result-item {
        padding: var(--spacing-sm);
    }
    
    .search-result-item h3 {
        font-size: 1rem;
    }
    
    /* 分页 */
    .pagination {
        flex-wrap: wrap;
        justify-content: center;
        gap: var(--spacing-xs);
    }
    
    .pagination a,
    .pagination span {
        padding: 6px 10px;
        font-size: 0.85rem;
    }
    
    /* 表单 */
    .form-group {
        margin-bottom: var(--spacing-sm);
    }
    
    .form-group input,
    .form-group select,
    .form-group textarea {
        padding: 10px;
        font-size: 16px; /* 防止iOS缩放 */
    }
    
    .btn {
        width: 100%;
        padding: 12px;
        font-size: 1rem;
    }
    
    /* 返回顶部 */
    .back-to-top {
        width: 40px;
        height: 40px;
        bottom: 20px;
        right: 20px;
    }
}

/* 小屏幕手机 (480px 及以下) */
@media (max-width: 480px) {
    :root {
        --spacing-lg: 1.5rem;
        --spacing-xl: 2.5rem;
    }
    
    body {
        font-size: 14px;
    }
    
    .logo {
        font-size: 1.2rem;
    }
    
    .logo span {
        display: block;
    }
    
    .hero {
        height: 280px;
    }
    
    .hero-title {
        font-size: 1.2rem;
    }
    
    .hero-excerpt {
        font-size: 0.85rem;
        display: none;
    }
    
    .section-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-sm);
    }
    
    .section-title {
        font-size: 1.1rem;
    }
    
    .article-card-image {
        height: 150px;
    }
    
    .article-card h3 {
        font-size: 0.95rem;
    }
    
    .article-card .excerpt {
        font-size: 0.85rem;
        display: none;
    }
    
    .issue-cover {
        height: 160px;
    }
    
    .issue-content h3 {
        font-size: 0.95rem;
    }
    
    .pricing-card {
        padding: var(--spacing-md);
    }
    
    .pricing-card .price {
        font-size: 1.8rem;
    }
    
    .team-member {
        padding: var(--spacing-sm);
    }
    
    .team-member img {
        width: 80px;
        height: 80px;
    }
    
    .timeline-item {
        padding-left: 40px;
    }
    
    .timeline-content {
        padding: var(--spacing-sm);
    }
    
    .footer {
        padding: var(--spacing-lg) 0;
    }
    
    .footer-bottom {
        flex-direction: column;
        gap: var(--spacing-sm);
        text-align: center;
    }
    
    /* 管理后台 */
    .admin-sidebar {
        width: 200px;
    }
    
    .admin-content {
        margin-left: 200px;
    }
    
    .admin-header {
        padding: var(--spacing-sm);
    }
    
    .admin-stats {
        grid-template-columns: 1fr;
    }
    
    .data-table {
        font-size: 0.85rem;
    }
    
    .data-table th,
    .data-table td {
        padding: 8px 6px;
    }
    
    .data-table th:nth-child(3),
    .data-table td:nth-child(3),
    .data-table th:nth-child(5),
    .data-table td:nth-child(5) {
        display: none;
    }
    
    @media (max-width: 768px) {
        .admin-sidebar {
            transform: translateX(-100%);
            transition: transform 0.3s;
        }
        
        .admin-sidebar.active {
            transform: translateX(0);
        }
        
        .admin-content {
            margin-left: 0;
        }
        
        .admin-header {
            justify-content: space-between;
        }
        
        .admin-header h1 {
            font-size: 1rem;
        }
    }
}